(1) Field of the Invention
The present invention relates to a sheet processing apparatus such as an image forming apparatus and the like having a sheet transport path, defined by the components which oppose either the obverse side or underside of a sheet-like paper, from a sheet feeder to a sheet output by way of a processor. In particular, the invention relates to a sheet processing apparatus having a configuration allowing for exposure of the sheet transport path to the outside of the apparatus in order to enable access to sheets in the case of sheet jamming or the like.
(2) Description of the Prior Art
There are sheet processing apparatuses such as image forming apparatuses, e.g., printer, copier and the like, which have a sheet transport path for conveying sheet-like paper from a sheet feeder to a sheet output by way of a processor whilst subjecting the sheet being conveyed along the sheet transport path to a predetermined process. In such sheet processing apparatuses, there are cases where the sheet being conveyed along the sheet transport path accidentally jams. In order to prevent reduction in operating efficiency of the sheet processing apparatus, it is necessary to enable quick and effective removal of the jammed paper from the sheet transport path.
For this purpose, there is a conventional sheet processing apparatus as shown in FIG. 1. In this configuration, an apparatus 200 has a side panel cover 201 on one side which is pivotally supported by a hinge 202 located on the rear side, and this side panel cover 201 has a component 203a fixed thereon which is one of the constituents of a paper transport path 203 and opposes one side of the sheet to be conveyed. Further, when side panel cover 201 is rotated outward with respect to apparatus 200, paper transport path 203 is made open. An example of component 203a constituting one side of paper transport path 203 is a transfer charger when the sheet processing apparatus is an image forming apparatus.
Japanese Patent Publication Hei 8 No. 18,724 discloses an image forming apparatus including a primary transport path for conveying a paper from a paper feeder to the paper output by way of a processor and an auxiliary transport path for inverting the paper, upside down in the apparatus so as to allow for duplex image forming on one sheet of paper. This apparatus comprises: a first unit having a side panel cover on one side thereof rotatably hinged at its bottom and being integrally provided with components opposing one side of the paper in the auxiliary transport path; and a second unit rotatably hinged at its bottom integrally having components opposing the other side of the paper in the auxiliary transport path and components opposing one side of the paper in the primary transport path, and arranged together with, or separately from, the first unit.
In accordance with the above conventional sheet processing apparatus, the component opposing one side of the paper in the paper transport path is rotated outward together with the side panel cover of the apparatus so as to open the paper transport path, thus allowing for easy removal of the jammed paper from the paper transport path.
However, in the conventional sheet processing apparatus shown in FIG. 1, in order to expose the entire part of paper transport path 203 to the outside, the width of side panel cover 201 rotatably arranged with respect to apparatus 200 needs to be at least greater than the width of the paper, perpendicular to the conveyed direction of the paper. Therefore, side panel cover 201 projects out a large amount from the side of apparatus 200, giving rise to a necessity of providing a large space for installation. Since component 203a which defines paper transport path 203 projects from the inner surface of side panel cover 201, when side panel cover 201 is rotated to the opened position, part of component 203a is located close to part of paper transport path 203 on the rear side, which gives rise to difficulties in removal of the paper from paper transport path 203 due to its interference with component 203a constituting paper transport path 203. Further, when a manual feeder tray 204 is attached to the side face of apparatus 200 for allowing manual paper feeding, manual feeder tray 204 projects to the rear when side panel cover 201 is rotated. Therefore, there is a need to provide enough space also on the rear side of apparatus 200, further increasing the space for installation.
In the configuration disclosed in Japanese Patent Publication Hei 8 No. 18,724, the first and second units are rotated relative to the apparatus about the hinge at the bottom thereof so as to release the primary and auxiliary transport paths. Therefore, the open amount is smaller on the lower side of the primary and auxiliary transport paths compared to that on the upper side, giving rise to difficulties in removing the paper jammed in the lower side of the primary and auxiliary transport paths. In particular, when the manual feeder tray is attached to the side face of the apparatus, the range of rotation of the first and second units is limited by the abutment between the manual feeder tray and the floor. Therefore, it is impossible to have a large angle of rotation of the first and second units relative to the apparatus, thus making more difficult the removal of the paper from the lower side of the primary and auxiliary transport paths.
Consequently, the conventional sheet processing apparatuses have suffered from inability of easy removal of jams without the necessity of providing a large space for installation of the apparatus.